Sweetness and Acidity

Title: The Sweetness and Acidity Level of Navel Orange

Problem Scenario

Broad Question

Specific Question:

Does the acidity level of a orange affect its sweetness?

Hypothesis:

The acidity level of the orange will be bigger if the sweetness is smaller, and be smaller if the sweetness is bigger. This is true because acidity makes the orange more sour, and the more the orange is sour, the less sweet it will be.

Graph of Hypothesis

Variables

Variables	Type of Variable
Acidity level	Independent
Sweetness	Dependent
Age of fruit, size of fruit	Control

Independent Variable:

Acidity Level

Dependent Variable:

Sweetness

Variables That Need To Be Controlled:

Age and Size of Fruit

Vocabulary List That Needs Explanation

Acidity: Sourness;tartness, the quality or state of being acid

Sweetness: Having the taste or flavor of characteristic of sugar, honey, etc.

pH testing strips: Scientific strips of paper used to test the acidity of an object using color.

Refractometer: A tool used to measure the sweetness of an object.

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General Plan

Potential Problems And Solutions:

Problem-not being able to bring tools home. Solution-Doing the experiment at school.

Safety Or Environmental Concerns:

None

Experimental Design

(add the correct headings from the experimental design page before beginning)

Resources and Budget Table

Item	Number needed	Cost	Where will I get this?
Refractometer	1	none	Mr. Littlefield
Oranges	About 3 of different ages	69 cents each	Hannaford
pH testing paper	1 pack	none	Mr. Littlefield

Detailed Procedure:

First of all, I will get out my materials-a refractometer, two cut-in-half oranges labeled 1, 2, and 3, and pH testing strips. All of the oranges will be from the same type of orange, but they will be different ages. I'll juice the 1st orange and then dip the testing strip in liquid #1 (the youngest orange) and record the color that came up. I then will do this for #2 and #3, and record THOSE colors on the same piece of paper. #2 will be the 2nd youngest one, and #3 will be the oldest. When I say oldest, I mean the age of the orange. Then I'll use my hydrometer to measure the sweetness of those three liquids (seperate). I'll record those results on the same sheet, make a graph, and do the science fair from there.

Diagram:

I don't have to

Photo List

Time Line

Data Table

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Data Analysis

All Raw Data-

Acidity (pH)	6 pH	5 pH	4 pH
Oz. of sugar per. gallon	21	16	14

	Looks and Feels	Smell	Insides
Old	~Soft/mushy areas ~Big ~Uneven Texture	~Sour ~Rotten	~Seperating at the center ~Very Juicy ~Mushy
Medium	~Even color ~Thin Skin	~Delicious ~Orangy/Citrusy	~Perfectly Juicy ~Center is firm and not coming apart
Young	~pale/dull in color ~smooth skin	~no smell	~not as juicy as others

Graphs:
see above graphs

Photos

Results- My results turned out exactly the opposite that I thought they would. The older oranges were more acidic than the younger ones. The older ones were also sweeter than the younger ones, but I'm not surprised about that.

Conclusion-

Does navel orange sweetness affect it's acidity? Yes, it does. When I tested three navel oranges, on every one of them, the sweetness level is higher than the acidity level. I saw a pattern in the acidity level that increased by 1 pH and a pattern in the sweetness that increased by about 2.

Discussion

~What patterns or trends did the data show?
~How strong is the relationship between the independent and dependent variables?
~Were you able to answer the experiment question? Yes, after my experiment.
~Did your experiment have any problems or did the data contain any errors? No, the data didn't contain any errors. The only problem I had was I forgot to take pictures of my experiment, so I have to do that soon.
~How could this experiment be improved upon or advanced? I really can't think of any ways that my experiment could be better, because I feel like I tried my best and did a good job on it.

Benefit to Community and/or Science-

My research could help scientists who are doing an expiriment with oranges or help people who want to make orange juice. Scientists, orange juice companies, or even just moms who want to make the perfect O.J. could use my data.

Background Research:

Young oranges are small and not to their full color yet. Perfect oranges have thin skin, they're heavy for their size, and has smooth, finely textured skin. Old oranges have faded coloring, soft spots, and wrinkled/grooved skin.

References

http://www.slate.com/articles/news_and_politics/explainer/2007/05/how_sweet_it_is.html

http://www.thefreedictionary.com/acidity

http://www.hannaford.com/catalog/search.cmd?keyword=navel%20orange

Abstract- In this experiment, I was trying to figure out if Acidity affected sweetness in navel oranges. I predicted that the acidity would be higher in the younger oranges because they are more tart and sour, and the sweetness would be higher in older oranges because they are older and more gushy and sweet than sour. I stuck pH (acidity) strips in old, medium, and young and then recorded it and stuck a hydrometer in the liquid and recorded that, too. To find out my results, read more.